Tetramorium species groups

It is convenient to organize species by region and species groups. This approach has been followed by most of the more informative taxonomic treatments of Tetramorium. The contents of this page are an attempt to organize information from various papers, as detailed in the list of references at the bottom of the page. There still remains much work to be done, with future taxonomy both adding to and potentially changing previous groups, arrangements and identification keys. With this in mind this page and other Tetramorium species groups webpages are provisional - and are not meant to represent a complete or definitive overview of this diverse and widely distributed genus.

Afrotropical

More than half of the 598 species in the genus are found in this region. A detailed list with all the species groups and species complexes can be found here: Afrotropical Tetramorium species groups

India

Agavekar et al. 2017 have shown the named species represent 12 species groups. Many more species remain to be described and our understanding of the diversity and taxonomy of this genus in the country is a work in progress.

See the Tetramorium of India page for more details.

Indo-Australian

Key to the Australian Tetramorium

Sorger (2011) - Tetramorium lucyae is a member of Bolton’s (1977) ciliatum-group defined by the following characters: “Antennae with 12 segments. Sting appendage triangular or dentiform. Anterior clypeal margin entire, not notched or indented medially. Frontal carinae extending back well beyond the level of the posterior margins of the eyes, ranging in development from feeble in Tetramorium curvispinosum to very strong in Tetramorium ciliatum. Propodeal spines long and usually strongly developed, never downcurved along their length. Gaster without modification as shown in mixtum group.” (Bolton 1977: 120). Bolton established this group as a “convenience group” and he mentioned several species within the group that he considered more closely interrelated than others, including Tetramorium ciliatum, Tetramorium flagellatum and Tetramorium tylinum; T. lucyae obviously also belongs in this species-complex. The remaining members of the ciliatum-group are: Tetramorium chapmani, T. curvispinosum, Tetramorium khnum and Tetramorium zypidum. All of the species of this group are distributed in the Oriental and Indo-Australian regions.

Malagasy

Key to Malagasy Tetramorium species groups

The species groups can be organized as per the following table (Hita Garcia and Fisher 2015):

Malagasy Species	Species Group	Zoogeography	Antennal segments	Sting shape	Anterior Clypeal Margin	Hita Garcia and Fisher publication	Habitat Affinities
6	bessonii	MAD	11	spatulate	notched	2012a	dry forests, savanna, grassland, anthropogenic habitats
8	bonibony	MAD	11	spatulate	notched	2012a	dry forests, savanna, grassland, anthropogenic habitats
10	dysalum	MAD	11	spatulate	notched	2012a	predominantly lowland or montane rainforests
2	kelleri	MAL	11	spatulate	notched	2012b	dry and humid forests
6	marginatum	MAD	11	spatulate	notched	2012a	lowland or montane rainforests
5	naganum	MAD	11	spatulate	notched	2014	lowland or montane rainforests
5	plesiarum	MAD	11	spatulate	notched	2014	dry forests, savanna, grassland
21	ranarum	MAD	11	spatulate	notched		predominantly lowland or montane rainforests
20	schaufussii	MAL	11	spatulate	notched	2014	mostly lowland or montane rainforests, rarely dry forests or open habitats
1	severini	MAD	11	spatulate	notched	2014	lowland or montane rainforests
2	tsingy	MAD	11	spatulate	notched	2012a	dry forest
22	tortuosum	NEA, AFR, MAD, ORI, INA	11	spatulate	notched	2012b	predominantly lowland or montane rainforests
1	weitzeckeri	AFR, MAL	11	spatulate	notched	2011	dry forests, savanna, grassland, anthropogenic habitats
3	bicarinatum	AFR, ORI, INA, MAL, T	12	triangular to dentiform	notched	2011	habitat generalist
1	obesum	ORI, INA, MAL, T	12	triangular to dentiform	notched	2011	habitat generalist
2	sericeiventre	AFR, MAL	12	triangular to dentiform	entire	2011	anthropogenic habitats, spiny forest, thicket, coastal and littoral forests, woodland
1	setigerum	AFR, MAD	12	triangular to dentiform	entire	2015	dry forest
7	simillimum	AFR, MAL, MAL, T	12	triangular to dentiform	entire		habitat generalist
2	tosii	MAD	12	triangular to dentiform	entire	2011	lowland or montane rainforests
125	Total

Tetramorium bessonii species group

An endemic Malagasy group.

Key to Tetramorium bessonii-group workers

Tetramorium bicarinatum species group

A number of species in this group are tramp species. There are three members of the group in the Malagasy region.

Tetramorium bonibony species group

Endemic to the Malagasy region, the group is comprised of 8 species.

Key to Tetramorium bonibony-group species

Tetramorium dysalum species group

All appear to be endemic to the Malagasy region.

Key to Tetramorium dysalum-group species

Tetramorium kelleri species group

Endemic to Madagascar and Mayotte, there are two species in this group.

Tetramorium marginatum species group

An endemic Madagascar group comprised of 6 species.

Key to Tetramorium marginatum-group species

Tetramorium naganum species group

Five species found in eastern and northern Madagascar.

Key to Tetramorium naganum-group species

Tetramorium obesum species group

The single member of this group that occurs in the Malagasy species is a well known, widespread tramp species.

Tetramorium lanuginosum

Tetramorium plesiarum species group

A small group of 5 species from the Malagasy region.

Key to Tetramorium plesiarum-group species

Tetramorium ranarum species group

An endemic species group only found in the Malagasy region that holds numerous valid and more than 25 tentatively undescribed species.

Tetramorium schaufussii species group

A Malagasy group that is divided into two species complexes.

Tetramorium cognatum species complex

Key to Tetramorium cognatum species complex workers

Tetramorium sericeiventre species group

This group is present in the Malagasy region in the form of two species, one of which is shared with the Afrotropical and Southern Palaearctic regions, while the other represents a new species (T. mahafaly) endemic to Madagascar.

Tetramorium setigerum species group

There is one species present in the Malagasy region.

Tetramorium cavernicola

Tetramorium severini species group

This species group contains a single endemic species, T. severini, that is one of the most conspicuous Tetramorium species in Madagascar.

Tetramorium severini

Tetramorium simillimum species group

This group includes species from other regions. Within the Malagasy region there are 5 described species and potentially 2 new species.

Tetramorium tortuosum species group

This group is widespread and present in most zoogeographic regions except the Palaearctic. Nevertheless, the highest species richness can be found in the Oriental and Indo-Australian regions while the Afrotropics and the New World are relatively species-poor. In the Malagasy region it is represented by about 20 species.

Key to Malagasy Tetramorium tortuosum-group workers

Tetramorium andrei species complex

Tetramorium jedi species complex

Tetramorium noeli species complex

Tetramorium smaug species complex

Tetramorium tosii species group

An endemic Madagascar species group.

Tetramorium tsingy species group

Endemic to a comparatively small area in Western Madagascar

Tetramorium weitzeckeri species group

This group is diverse in the Afrotropical region: Afrotropical Tetramorium weitzeckeri species group. The sole representive in the Malagasy region also occurs in the Afrotropics.

Tetramorium humbloti

Species group identification key images from Hita Garcia and Fisher (2011)

New World

These are a mix of Tetramorium tortuosum-group species (T. azcatltontlium, T. bicolorum]], T. hispidum]], T. mexicanum, T. notomelanum, T. placidum, and T. spinosum) and introduced species (T. atratulum, T. bicarinatum, T. caldarium, T. immigrans, T. insolens, T. lanuginosum, T. pacificum, T. simillimum and T. tsushimae.

There is a key to the United States species that includes the introduced and native species:

Key to Tetramorium species of the United States

and a Tetramorium tortuosum-group species key:

Key to Tetramorium tortuosum-group species of the New World

Palaearctic

See Steiner et al., 2005; Schlick-Steiner et al., 2006a; Csösz et al., 2007; Csösz & Schulz, 2010; Steiner et al., 2010, Wagner et al. 2017.

Tetramorium judas
Tetramorium semilaeve jugurtha
Tetramorium caespitum maura
Tetramorium davidi
Tetramorium schmidti
Tetramorium sp. 1
Tetramorium sp. 2

Tetramorium inquilinum species group

References